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<FONT color="green">001</FONT>    package gates;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    import mathtools.Complex;<a name="line.3"></a>
<FONT color="green">004</FONT>    import mathtools.Matrix;<a name="line.4"></a>
<FONT color="green">005</FONT>    import register.Register;<a name="line.5"></a>
<FONT color="green">006</FONT>    <a name="line.6"></a>
<FONT color="green">007</FONT>    /**<a name="line.7"></a>
<FONT color="green">008</FONT>     * Matrix representation of a iI gate.<a name="line.8"></a>
<FONT color="green">009</FONT>     * This implements Gate interface, so consult this for public methods.<a name="line.9"></a>
<FONT color="green">010</FONT>     * The constructor for this gate is protected, so generating such an object is left<a name="line.10"></a>
<FONT color="green">011</FONT>     * for the factory class &lt;code&gt;Factory&lt;/code&gt;<a name="line.11"></a>
<FONT color="green">012</FONT>     * @author Richard Inskip, Jan Zaucha<a name="line.12"></a>
<FONT color="green">013</FONT>     *<a name="line.13"></a>
<FONT color="green">014</FONT>     */<a name="line.14"></a>
<FONT color="green">015</FONT>    public class ComplexIdentityMatrix extends MatrixGate{<a name="line.15"></a>
<FONT color="green">016</FONT>    <a name="line.16"></a>
<FONT color="green">017</FONT>            /** Complex identity matrix i*I */<a name="line.17"></a>
<FONT color="green">018</FONT>            private Matrix ComplexIdentity;<a name="line.18"></a>
<FONT color="green">019</FONT>    <a name="line.19"></a>
<FONT color="green">020</FONT>            /** Store the target qubit the gate acts on*/   <a name="line.20"></a>
<FONT color="green">021</FONT>            private int target;<a name="line.21"></a>
<FONT color="green">022</FONT>    <a name="line.22"></a>
<FONT color="green">023</FONT>            /**<a name="line.23"></a>
<FONT color="green">024</FONT>             * protected constructor to instantiate this object<a name="line.24"></a>
<FONT color="green">025</FONT>             * @param target A flag to apply singly or to all the Qubits.<a name="line.25"></a>
<FONT color="green">026</FONT>             */<a name="line.26"></a>
<FONT color="green">027</FONT>            protected ComplexIdentityMatrix(int target){<a name="line.27"></a>
<FONT color="green">028</FONT>                    ComplexIdentity = Matrix.IdentityMatrix(2).multiplyMatrix(new Complex(0,1));<a name="line.28"></a>
<FONT color="green">029</FONT>                    this.target = target;<a name="line.29"></a>
<FONT color="green">030</FONT>            }<a name="line.30"></a>
<FONT color="green">031</FONT>    <a name="line.31"></a>
<FONT color="green">032</FONT>            /**<a name="line.32"></a>
<FONT color="green">033</FONT>             *  Apply Method to apply the gate to a register.<a name="line.33"></a>
<FONT color="green">034</FONT>             */<a name="line.34"></a>
<FONT color="green">035</FONT>            public void apply(Register r) {<a name="line.35"></a>
<FONT color="green">036</FONT>                    int numQubits = r.getNumQbits();<a name="line.36"></a>
<FONT color="green">037</FONT>                    ComplexIdentity = ComplexIdentity.tensorProduct(Matrix.IdentityMatrix((int)Math.pow(2,(numQubits-1))));<a name="line.37"></a>
<FONT color="green">038</FONT>    <a name="line.38"></a>
<FONT color="green">039</FONT>                    if(target==-1){<a name="line.39"></a>
<FONT color="green">040</FONT>                            ComplexIdentity.powerMatrix(numQubits);<a name="line.40"></a>
<FONT color="green">041</FONT>                            r.update(ComplexIdentity.multiplyMatrix(r));<a name="line.41"></a>
<FONT color="green">042</FONT>                    }<a name="line.42"></a>
<FONT color="green">043</FONT>                    else{<a name="line.43"></a>
<FONT color="green">044</FONT>                            r.update(ComplexIdentity.multiplyMatrix(r));<a name="line.44"></a>
<FONT color="green">045</FONT>                    }<a name="line.45"></a>
<FONT color="green">046</FONT>    <a name="line.46"></a>
<FONT color="green">047</FONT>            }<a name="line.47"></a>
<FONT color="green">048</FONT>    <a name="line.48"></a>
<FONT color="green">049</FONT>    <a name="line.49"></a>
<FONT color="green">050</FONT>            /** Return the name of this gate<a name="line.50"></a>
<FONT color="green">051</FONT>             * @return name<a name="line.51"></a>
<FONT color="green">052</FONT>             */<a name="line.52"></a>
<FONT color="green">053</FONT>            public String getName() {<a name="line.53"></a>
<FONT color="green">054</FONT>                    return "Complex Identity";<a name="line.54"></a>
<FONT color="green">055</FONT>            }<a name="line.55"></a>
<FONT color="green">056</FONT>    <a name="line.56"></a>
<FONT color="green">057</FONT>    <a name="line.57"></a>
<FONT color="green">058</FONT>    }<a name="line.58"></a>




























































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